A conventional golf club has a tapered shaft, the larger end having a grip used for a handle, and the smaller end is connected to a head used for striking a ball. The head is heavy compared to the shaft. A steel shaft, not including the rubber grip, is about 110 gm. The head is about 210 gm for a #1 wood which is the driver for the longest distance. Even for the so-called irons, which are medium range golf club, the head is still much heavier than the shaft. The reason for a heavy head is that the greater momentum upon hitting the ball will drive the ball farther.
Among design parameters, besides the length and the taper of the shaft, its weight distribution and shape of the head, another important design parameter is the so called angle of the hitting face of the head. Hitting face is the generally flat surface of the head which provides the impact surface with the ball. The tangent plane of the hitting face is the tangent plane at the point on the face with the minimum curvature. The tangent plane is an inclined plane, making an angle with the axis of the golf club and is also tilted with respect to the ground when the golf club is held in position ready to strike. The tilting angle of the hitting face is responsible for the ball to fly at an inclined angle to the ground level. If the hitting face angle is zero, the ball will travel parallel to the ground level. This tilting angle varies from several degrees to twenty degrees or more. Different golf club manufactures have different ways and conventions to define that angle. Since the golf club is a slender, tapered shaft which is flexible and with most of the curvature during swinging is derived from the slender part of the shaft near the head, the true inclination angle the hitting face of the head is making with respect to the ball when it hits is an unknown. Most likely it is a much greater angle than what is designed for.
It is known that the swing of a golf club lasts only a fraction of a second, about 3 to 4 tenth of a second, before the head hits the ball. The impact lasts only about 0.001 second or even less. In that short time period, it is not possible to have an on-course correction of the swing of the shaft to maneuver it so that when the ball is hit, the shaft is straight and the head is hitting at the ball at an angle equal to the angle of the hitting face. Only through practice, a golfer will know how to swing the golf club and how much force is to be applied for the desired optimum condition. Each pro has its own ways to compensate for this problem, but for the majority of ordinary players, their scores vary from day to day due to this difficulty.
The present invention explains what is going on in that fraction of a second during the swing of the golf club and proposes to have a facilitating means in the golf club that will automatically improve the control of the inclination angle of the hitting face of the head at impact time so that every swing turns out to be a good swing for ordinary players .